From: Reid Kleckner <rnk@google.com>
Date: Tue, 18 Aug 2015 23:18:57 +0000 (+0000)
Subject: Merge r244488 to the 3.7 release branch
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7e3411cfc41df40eabcbe9fcefff08822027da0a;p=clang

Merge r244488 to the 3.7 release branch

It avoids doing key function optimizations when the key function is
dllimported.

Fixed PR24409.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_37@245388 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index 388c91c9cb..de7bcb826e 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -2014,6 +2014,12 @@ static const CXXMethodDecl *computeKeyFunction(ASTContext &Context,
         continue;
     }
 
+    // If the key function is dllimport but the class isn't, then the class has
+    // no key function. The DLL that exports the key function won't export the
+    // vtable in this case.
+    if (MD->hasAttr<DLLImportAttr>() && !RD->hasAttr<DLLImportAttr>())
+      return nullptr;
+
     // We found it.
     return MD;
   }
diff --git a/test/CodeGenCXX/dllimport-rtti.cpp b/test/CodeGenCXX/dllimport-rtti.cpp
index f2d1bec95c..6fe67daa38 100644
--- a/test/CodeGenCXX/dllimport-rtti.cpp
+++ b/test/CodeGenCXX/dllimport-rtti.cpp
@@ -20,3 +20,11 @@ struct __declspec(dllimport) V {
   virtual void f();
 } v;
 // GNU-DAG: @_ZTV1V = external dllimport
+
+struct W {
+  __declspec(dllimport) virtual void f();
+  virtual void g();
+} w;
+// GNU-DAG: @_ZTV1W = linkonce_odr
+// GNU-DAG: @_ZTS1W = linkonce_odr
+// GNU-DAG: @_ZTI1W = linkonce_odr